๐ค AI Summary
Slot Attention (SA) faces two key challenges in object-centric learning: (1) cold-start queries for the first frame of images/videos lack sample-specificity, leading to imprecise object aggregation; and (2) subsequent video frames reuse the same query update strategy as the first frame, ignoring their inherent sample-awareness. This paper proposes SmoothSA, the first SA variant to introduce a self-distillation-based query warm-up mechanism that leverages image content to enhance initial queries for the first frame. Additionally, we design a heterogeneous iterative strategy: three full iterations for the first frame versus a single refinement step for subsequent framesโtailored to their distinct representational properties. SmoothSA significantly improves object separation accuracy and temporal consistency, outperforming existing SA variants across multiple object discovery, recognition, and downstream tasks.
๐ Abstract
Slot Attention (SA) and its variants lie at the heart of mainstream Object-Centric Learning (OCL). Objects in an image can be aggregated into respective slot vectors, by extit{iteratively} refining cold-start query vectors, typically three times, via SA on image features. For video, such aggregation is extit{recurrently} shared across frames, with queries cold-started on the first frame while transitioned from the previous frame's slots on non-first frames. However, the cold-start queries lack sample-specific cues thus hinder precise aggregation on the image or video's first frame; Also, non-first frames' queries are already sample-specific thus require transforms different from the first frame's aggregation. We address these issues for the first time with our extit{SmoothSA}: (1) To smooth SA iterations on the image or video's first frame, we extit{preheat} the cold-start queries with rich information of input features, via a tiny module self-distilled inside OCL; (2) To smooth SA recurrences across all video frames, we extit{differentiate} the homogeneous transforms on the first and non-first frames, by using full and single iterations respectively. Comprehensive experiments on object discovery, recognition and downstream benchmarks validate our method's effectiveness. Further analyses intuitively illuminate how our method smooths SA iterations and recurrences. Our code is available in the supplement.